This invention relates generally to optical coupling of light sources and fiber optics cables, or light pipes; and more particularly concerns optical coupling of lens units and light fibers in such a way as to position the cable to receive light transmission from a light source spaced endwise from the light source, such as an LED.
There is need for improved apparatus and method to overcome difficulties in optical coupling as between light sources, light pipes and lenses.
IT is a major object of the invention to provide improvements in such optical coupling as will meet the referenced need. Basically a light transmission device in accordance with the invention comprises:
a) a fiber optics cable having light entrance and light exit ends,
b) structure including a body receiving the entrance end of the light pipe for positioning the entrance the to receive light,
c) the structure including a receiver in the body,
d) and at least one anchor carried by the structure to a mounting board, for positively positioning the structure, body and receiver, relative to the board.
It is another important object to provide a portion of the structure to be sidewardly offset relative to the receiver, the one anchor being in substantial alignment with the portion of the structure, and there being a shoulder on said one portion of the structure in substantial alignment with the anchor to receive pushing force transmission from a tool to drive the anchor toward an opening in said board.
Another object is to provide a tool receiving recess in said structure, the shoulder being associated with that recess.
A further object is to provide a light focusing and transmitting lens located in the structure in alignment with the entrance end of the light pipe.
In this regard the lens and receiver are preferably unitary, for simplicity; and the light source is preferably in the form of an LED located in a cavity in the body, in alignment with the receiver.
Yet another object is to provide multiple of the anchors projecting from a mounting surface defined by said structure, the anchors offset from an axis defined by the receiver, totally support the structure.
An additional object is to provide the body to have multiple sides, two of which form tongue and groove configurations to receive corresponding groove and tongue elements of adjacently mounted bodies.
Yet another is to provide a lens unit at the light exit end of the cable; the lens unit preferably having a light transmitting end wall, and a side wall extending away from that end wall, the cable light exit end retained in assembled relation to that side wall, whereby light is transmitted from the cable exit end to said lens unit end wall.
A yet additional object includes provision of a tubular retainer receiving the light exit end of the cable, the tubular retainer assembled to the lens unit side wall. That side wall preferably has multiple spring fingers, and said retainer and fingers have interlocking relation. The retainer and fingers typically have tongue and groove interlocking relation. As will be seen, the retainer preferably has an exterior flange or ring, and at least one of said fingers has a groove receiving at least part of the flange.
Further, the spring fingers preferably have cam surfaces thereon to be spread apart in response to axial movement of the retainer relative to the spring fingers.
A yet further object includes a support panel carrying said LED, and another support panel supporting said lens unit said panels spaced apart in fixed relation.
An additional object is to provide:
a) a fiber optics cable having light entrance and light exit ends,
b) a lens unit at the light exit end of the cable, said unit having a light transmitting end wall, a side wall extending away from said end wall, the cable light exit end retained in assembled relation to said side all, whereby light is transmitted from the cable exit and to said lens unit end wall,
c) and a tubular retainer receiving said light exit end of the cable, to position the cable exit end relative to the unit end wall whereby that end wall is substantially fully illuminated by light from the cable, the tubular retainer assembled to said side wall.
As will be seen, the side wall and cable (or light pipe) exit end may have interlocking relation; the side wall may provide multiple retention fingers; the retainer may have an exterior flange, and at least one of the finger may have a groove receiving at least part of the flange; and the fingers may have cam surfaces to be deflected in response to axial movement of the retainer relative to the fingers. Also, the retainer position the cable exit end relative to the lens unit end wall, whereby that end wall is substantially fully illuminated by light from the cable exit end.
Further objects include provision of a light focusing and transmitting lens located in said structure in alignment with said entrance and of the light pipe; the lens having a substantially flat light exit surface to align with the cable core; the cable having a plastic jacket surrounding said core, said jacket retained to a bore defined by the receiver; and cable retention elements on the receiver that carries the lens and receives the cable entrance end.
These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which: